Mitt Romney is set to depart from London today. After three days of photo ops and closed meetings, the likely next Republican presidential nominee met prime ministers past and present. He attended the Olympic Games' opening ceremony, and he raised some serious cash. But Mr. Romney, who ran the 2002 Winter Olympic Games - in Salt Lake City - managed to deliver an assessment of London's handling of the Olympics that drew a rebuke from Prime Minister David Cameron. That probably wasn't on the candidate's agenda.

Gideon Rachman is the chief foreign affairs columnist for the Financial Times, and he's been following Gov. Romney's visit to London. And he joins us from London. Gideon, thanks for being with us.

GIDEON RACHMAN: My pleasure.

SIMON: And maybe we should remind ourselves - what, exactly, did Mitt Romney say in this interview?

RACHMAN: Yeah, he was asked whether he felt confident that London was going to handle the Olympics fine. And rather than giving the kind of standard, bland reply, he made the mistake of actually answering the question honestly, and said that there were disconcerting signs - to use his phrase - that some things weren't going very well, and pointed to the problems that we have had hiring security guards for the Games - they had to, in the end, draft in a lot of troops; and mentioned the threat of a strike at Customs, which actually didn't materialize; and said, well, it's hard to know just how well it is going to go.

And actually, that's the kind of thing that people in London itself have been saying for months. But somehow, coming from a foreigner - and a prominent foreigner - it provoked a bit of a backlash in London. And Cameron then replied rather tartly, by saying well, it's much easier if you're going to hold the Olympics in the middle of nowhere - which was felt to be a reference to Salt Lake City.

SIMON: And Boris Johnson, the mayor of London who by some accounts, is the most - certainly the most popular Conservative Party member in the country, actually, by name disputed Mr. Romney in a public ceremony. Now, Boris Johnson is a conservative; they should be pals.

RACHMAN: Absolutely. Well, Boris Johnson is actually, above all, a populist. And I think what he spotted was an opportunity to have a go at a guy who people haven't particularly heard of; but also, to buoy up Londoners 'cause in fact, Johnson himself had said a couple of weeks ago that London was in danger of having a nervous breakdown about the anxieties that things would go badly. There have been a lot of stories, which was, obviously, what Romney picked up on.

But I think the night before the Games, he was sort of - you know, keying up the crowd by saying, you know, there's this guy, Mitt Romney, who says we might not be ready. Are we ready? And then, of course, you get a big cheer back. But of course, it's - if not a political risk, it's politically unusual to take on somebody who may, after all, be the president of the United States in a few months' time.

SIMON: You know American politics. Mitt Romney is not running for president of Great Britain. So how harmful do you think this is, really?

RACHMAN: You know, there's going to be a huge amount that happens between now and November. And the idea that a few, kind of negative headlines in the London papers will still be reverberating then, seems to me unlikely. There is, however, an irony, I think. If you look at the Romney campaign and the kind of things they've been saying, their argument is that Obama has actually antagonized traditional allies.

Romney has a foreign policy adviser, guy called Nile Gardiner, who compiles lists of snubs that Obama has allegedly dished out to the British. These, I should add, are snubs that the British generally haven't noticed. They were removing Churchill's bust from the Oval Office; not absolutely, unequivocally, taking Britain's side in the argument with Argentina over the Falkland Islands; that kind of thing. I mean, as I say, there's not that sort of impression in Britain, that Obama is anti-British in any way, particularly. But it's kind of funny that given that Romney had been about to play that card, that he then puts his foot in it.

SIMON: Let me ask you a little bit about British reaction. Has it been a huge story there?

RACHMAN: Yeah, it has, actually - I think partly because it's funny; and because Romney is a slightly stiff individual, and so he looks a bit of an easy target. I also think that Romney inadvertently kind of played into this neurosis that Boris Johnson referred to. I mean, the fact is that Londoners and Brits have been very worried about how these games are going to go, and still are.

But it's a bit like if you were about to take a crucial exam and you, yourself, were worried that you might mess it up; and somebody walked into your room and said - rather than saying oh, don't worry, it'll go fine, said actually, yeah, I can see why you're worried, that really could go wrong. You would react quite badly. And I think that was sort of what Romney did. But I would be surprised if this story, as they say, has legs. This was more a sort of, you know, kind of gaffe level. I think; we'll see.

SIMON: Gideon Rachman, chief foreign affairs columnist for the Financial Times, speaking with us from London. Thanks very much